CLOSED-CELL TANNIN-BASED FOAMS

摘要

Disclosed are foam compositions and processes to form closed-cell tannin-based foams. The process comprises forming an agglomerate-free solution comprising a tannin, a first monomer, a second monomer, and water, wherein the first monomer comprises formaldehyde, paraformaldehyde, furfural, glyoxal, acetaldehyde, 5-hydroxymethylfurfural, acroleim, levulinate esters, sugars, 2,5-furandicarboxylic acid, 2,5-furandicarboxylic aldehyde, urea, difurfural (DFF), or mixtures thereof, and the second monomer comprises furfuryl alcohol, glycerol, sorbitol, lignin, or mixtures thereof. The process also comprises mixing one or more blowing agents with the agglomerate-free solution to form a pre-foam mixture and mixing an acid catalyst with the pre-foam mixture to form a foam composition. The process comprises adding a surfactant to at least one of the agglomerate-free solution, pre-foam mixture, or the foam composition. The process further comprises processing the foam composition to form a tannin-based foam.